It is proposed to study the development of the dental lamina by surgical transplantation of tooth germs and dental lamina in the Australian marsupial Trichosurus vulpecula. Radiographic and histological analyses will be performed. The role of basement membrane and basal lamina in dental entogeny will be investigated by various enzymatic separation techniques with subsequent heterologous recombinations cultured on the CAM. Cell culture studies on the role of various cell populations within the dental pulp during differentiation and repair will be continued. BIBLIOGRAPHIC REFERENCES: Miller, W. A. and Munaco, F.S. 1977. Responses of primary bovine cultures to endodontic materials. J. Endodont. - in manuscript. Everett, M. M. and Miller, W. A. 1977. A polyacid dichrome suitable for staining monolayer tissue cultures. In Vitro - in manuscript.